This invention relates to oil flow sensing.
In a two-cycle outboard marine engine, for example, lubricating oil flows in pulses, rather than continuously. The oil may be pumped by a solenoid that is triggered by an electrical signal from an engine control module (ECM). The pulses occur at a rate that depends on engine speed and may be as high as 4 Hz or higher or as low as 0.007 Hz with a pulse duration of about 40 milliseconds.
One way to make sure that oil is always reaching the parts of the engine that need lubrication is to include level switches in an oil reservoir. When the level of the oil falls unacceptably low, an alarm can be triggered or the engine can be stopped.